The Oxford University Wild Swimming society has been forced to cancel all swims for the foreseeable future after increased levels of E. Coli bacteria were found in Hinksey Lake. This follows heavy rainfall and flooding, caused by Storm Henk on the 2nd of January 2024, closing roads, causing rivers to burst their banks, and leading to houses being evacuated. E. Coli infection causes symptoms such as stomach cramps, fever and diarrhoea; most adults recover quickly but infection can be more serious. 

Oxford, a city with a plethora of rivers and lakes in walking distance of its urban centre, has typically been a haven for wild swimming. Hinksey Lake and Port Meadow are popular spots throughout the year, with wild swimmers praising the pastime for both physical and mental health benefits, and its low-cost simplicity. A study in the British Medical Journal Case Reports even suggested that cold water swimming could be an effective treatment for depression, with the shock of the cold water adapting the body to cope with stress responses prompted by depression and anxiety. However, as only two out of 48 waterbodies in Oxford are classed as being in ‘good’ ecological health, this hobby is facing significant difficulty, worsened by frequent sewage discharges.

Wolvercote Mill Stream in Port Meadow, a common spot for the Oxford Wild Swimming group, achieved designated bathing water status in April 2022, however by the end of 2023 it had been ranked ‘poor’ by the Environment Agency for the third consecutive year. The primary cause of the stream’s bad ratings has been the persistently high levels of sewage released into the water by an upstream sewage plant. If it achieves a ‘poor’ ranking for five consecutive years, it could lose its special status, meaning the Environment Agency would no longer be required to test the stream for bacteria pollution every week in summer.

The water quality in Oxford has been causing problems for a while. Responsively, Oxford Academic Dr Alex Lipp recently put together a sewage map, revealing worryingly high levels of sewage being discharged into Oxfordshire waterways. This poses a great threat to the health and biodiversity of Oxford rivers as phosphates and nitrates within the sewage contribute to the pollution. The waterways of Oxford host a great variety of freshwater plants and animals, many of which have already disappeared from the area, unable to cope with the increasing pollution levels. In 2016, Freshwater Habitats Trust reported that the Oxford area was the last place in England where a Glutinous Snail was recorded, a species whose population has decreased across Europe. The problems with sewage discharge and rising levels of pollution are increasingly damaging Oxford’s status as a freshwater biodiversity hotspot.

Protests against the dumping of raw sewage have occurred frequently in recent years, with around 200 people gathering in January 2022 after a late warning of a discharge meant that swimmers swam through raw sewage on Christmas Day. 

This recent discovery of E. Coli at Hinksey is another blow to the local wild swimming community, with Oxford City Council even declaring that they “strongly advise against wild swimming”. Flood prevention is a continual focus of the council, with the ‘Oxford Flood Scheme’ being created with the intention to manage and alleviate flood risk in the city for the next 100 years. This scheme intends to create a wetland wildlife corridor to create more space for floodwater to drain from built-up areas. In response to the flooding from Storm Henk, the council announced on January the 11th that more than four million litres of water were pumped every 24 hours for a week, helping to tackle the rising water levels.